Chapter 3 - Biological molecules: the carbon compounds of life Flashcards
Hydroxyl Group
(OH) group consisting of an oxygen atom linked to a hydrogen atom on one side and to a carbon chain on the other side
Carbonyl group
(C=O) the reactive part of aldehydes and ketones, consisting of an oxygen atom linked to a carbon atom by a double bond
Carboxyl group
(COOH) the characteristic functional group of organic acids, formed by the combination of carbonyl and hydroxyl groups
Amino group
(NH2) group that acts as an organic base, consisting of a nitrogen atom bonded on one side to 2 hydrogen atoms and on the other side to a carbon chain
Phosphate group
(OPO3~2-) Group consisting of a central phosphorus atom held in 4 linkages:
- 2 that bind OH groups to the central phosphorus atom
- a 3rd that binds an oxygen atom to the central phosphorus atom
- a 4th that links the phosphate group to an oxygen atom
Sulfhydryl group
(SH) group that works as a molecular fastener, consisting of a sulfur atom linked on one side to a hydrogen atom and on the other side to a carbon chain
Disulfide linkage
(-S-S-) linkage that occurs when 2 sulfhydryl groups interact during a linking reaction
organic molecules
molecule based on carbon
Inorganic molecules
molecule without carbon atoms in its structure
Hydrocarbon
molecule consisting only of carbon atoms and hydrogen atoms bonded to each other and themselves (C2H6)
Chemical evolution
the formation of the organic molecules that allowed the first forms of life on Earth to originate
functional group
small, reactive groups of atoms. The functional group determines the chemical behavior of the compound
Isomers
2 or molecules with the same chemical formula but different molecular structures
Stereoisomers
molecules that are mirror images of one another are an example of stereoisomers
Structural isomers
2 molecules with the same chemical formula but atoms that are arranged in different ways
Condensation reaction (also referred to as a dehydration synthesis reaction)
reaction during which the components of a water molecule are removed, usually as part of the assembly of a larger molecule from smaller sub-units
Hydrolysis
reaction in which the components of a water molecule are added to functional groups as molecules are broken into smaller subunits
Polymer
a molecule assembled from subunit monomer molecules into a chain by covalent bonds
Polymerisation
the process of assembly of a polymer from monomers
Macromolecule
a single polymer molecule with a mass of 1000 Da (Daltons) or more
Starch
a storage polysaccharide in plants consisting of branched or unbranched chains of glucose subunits
Glycogen
energy-providing carbohydrates stored in animal cells
cellulose
one of the primary constituents of plant cell walls, formed by chains of carbohydrate subunits
Monosaccharide
the smallest carbohydrates, containing 3 to 7 carbon atoms
disaccharide
a carbohydrate consisting of 2 monosaccharides bonded together by a Glycosidic bond
Polysaccharide
carbohydrate polymers with more than 10 linked monosaccharide monomers
Glycosidic bond
bond formed by the linkage of two alpha glucose molecules with oxygen as a bridge between a carbon of the first glucose unit and a carbon of the second glucose unit
oil
neutral lipid that is liquid at biological temperatures
fat
neutral lipid that is semisolid at biological temperatures
triglyceride
a non-polar compound produced when a fatty acid binds by a dehydration synthesis reaction at each glycerol’s 3 OH bearing sites
fatty acid
1 or 2 components of a neutral lipid, containing a single hydrocarbon chain with a carboxyl group linked at one end
ester linkage
a covalent bond formed between a carboxyl group and a hydroxyl group
saturated
With respect to a fatty acid, if only single bonds link the carbon atoms.
With respect to an enzyme reaction, when the enzyme is cycling as rapidly as possible so that further increases in substrate concentration have no direct effect on the reaction rate
unsaturated
with respects to a fatty acid, if one or more double bonds link the carbon atoms
monounsaturated
fatty acids with 1 double bond
polyunsaturated
fatty acid with more than one double bond
wax
a substance insoluble in water that is formed when fatty acids combine with long chain alcohols or hydrocarbon structures
phospholipids
a phosphate-contain lipid
steroid
a type of lipid derived from cholesterol
sterol
steroid with a single polar OH group linked to one end of the ring framework and a complex, non-polar hydrocarbon chain at the other end
cholesterol
the predominant sterol of animal cell membranes
enzymes
protein that accelerates the rate of a cellular reaction
peptide bond
a linked by a dehydration synthesis reaction between the amino group of one amino acid and the carboxyl group of the second
N-terminal end
the end of a polypeptide chain with an NH3~+ group
C-terminal end
the end of an amino acid chain with a COO~- group
polypeptide
the chain of amino acids formed by sequential peptide bonds
primary structure
the particular and unique linear sequence of amino acids linked to each other by peptide bonds to form a polypeptide
Secondary structure
the coiling or the folding of a segment of a polypeptide chain produced by hydrogen bonding between different amino acids in the segment. Alpha helices and beta strands are examples of secondary structure
tertiary structure
the folding of the complete amino acid sequence of a polypeptide chain, with its secondary structures, into the overall 3 dimensional shape
quaternary structure
the arrangement of bonded polypeptide chains in a protein that contains more than one chain
alpha helix
a type of secondary structure of a polypeptide in which the amino acid chain is twisted into a regular, right-hand spiral
beta sheet
a type of primary structure in a polypeptide in which the amino acid chain zigzags in a flat plane to form a beta strand, and beta strands then align side by side in the same/ opposite direction
conformation
the overall 3 dimensional shape of a protein
denaturation
a loss of both the structure and function of a protein due to extreme conditions that unfold it from its normal conformation
renaturation
the reformation of a denatured protein into its folded, functional state
chaperone proteins ( or chaperonin)
‘Guide’ protein that binds temporarily with newly synthesized proteins, directing their conformation toward the correct tertiary structure and inhibiting incorrect arrangements as the new proteins fold
conformational change
alteration in the 3 dimensional shape of a protein
domains (2)
- In protein structure, a distinct, large structural subdivision produced in many proteins by the folding of the amino acid chain.
- In systematics, the highest taxonomic category, a group of cellular organisms with characteristics that set it apart as a major trunk of the Tree of Life
DNA
the large, double stranded, helical molecule that is the genetic material of all living organisms
RNA
a polymer assembled from repeating nucleotide monomers in which the 5-carbon sugar is ribose. Cellular RNAs include mRNA (which is translated to produce a polypeptide), tRNA (which brings an amino acid to the ribosome for assembly into a polypeptide during translation), and rRNA (which is a structural component of ribosomes).
The genetic material of some viruses is RNA
Nucleotide
the monomer of nucleic acids, consisting of a 5 carbon sugar, a nitrogenous base and a phosphate
Nitrogenous base
a nitrogen-containing molecule that accepts protons
Pyrimidines
a type of nitrogenous base with on carbon-nitrogen ring
Purine
a type of nitrogenous base with 2 carbon-nitrogen rings
Deoxyribonucleotide
nucleotide containing deoxyribose as the sugar, deoxyribonucleotides are components of DNA
ribonucleotide
nucleotide contain ribose as the sugar; ribonucleotides are components of RNA
nucleoside
molecule containing only a nitrogenous base and a 5 carbon sugar
phosphodiester bond
the linkage of nucleotides in polynucleotide chains by a bridging phosphate group between the 5’ carbon of one sugar and the 3’ carbon of the next sugar in line
template
a nucleotide chain used in DNA replication for the assembly of a complementary chain
